The present invention relates generally to a manufacturing process of an IC module, and more particularly to a manufacturing process that can reduce the manufacturing cost of IC module and enhance the repairing speed for changing its chip.
According to the conventional manufacturing process of IC module, it first assembles IC chips that have been fully encapsulated and tested to a printed circuit board, and then tests the module to finish the IC module manufacturing. Taiwan patent No. 98,736 (publication No. 344,853) discloses a different manufacturing process of IC Module. It directly assembles IC chips to a printed circuit board, and then the chips are electrically connected to the circuit board by bonding wires. Finally, the chips are encapsulated by synthesis resin on the circuit board. Such a manufacturing process can adopt one-off manufacturing process from assemblage to module product. It is more simple and timesaving than the conventional process, which has to adopt multiple section divided process in IC encapsulation, IC testing and module assembly. However, the process disclosed in the foregoing Taiwan patent does not assemble the electronic elements until the chips have been bonded and encapsulated. Therefore, not only it is easy to cause the problems that the chip is damage, the bonding wires break and the encapsulation is distorted to increase the ineligible rate of the whole module, but also it is not easy to repair and replace the ineligible chips because the chips have been encapsulated in advance.
Taiwan patent No. 118,728 (publication No. 396,553) was filed by the present applicant to solve the above problems. However, no matter the patent No. 98,736, or the patent No. 118,728 in Taiwan, R.O.C., both of them assemble the IC chips on the printed circuit board directly for wire bonding, so the whole circuit board should be specially arranged so as to ensure a firmer connections between the conductor pattern of the printed circuit board and the bonding wires. For example, if the gold bonding wire is used as the electronic connecting bridge, the connecting portion of the conductor pattern of the circuit board should be specially gilded, so that the manufacturing cost of the circuit board will relatively increase. Next, if the chip has to be changed for repair, both of the two Taiwan patents have to remove the bonding wires that connect the conductor pattern of the circuit board and the chip one by one, then take the old chip away and assemble the new one, finally bond the wire. Consequently, the efficiency of changing the chip sometimes is not high. Moreover, it is quite possible to peel off the gilding of the conductor pattern of the circuit board at the time when the bonding wires are removed, so that the circuit board cannot be reused; consequently, the action to change the chip should be taken carefully, which further affected the speed of the repair action. Otherwise, both the two inventions may adopt the flip chip technology to connect the chip and the circuit board electronically to get rid of the shortcomings of the above-mentioned wire bonding connection method. However, no matter the wire bonding method or flip chip method to connect the circuit board and the chip, once the chip has been encapsulated by the isolating resin, it is rather difficult to replace it, which affects the speed of the repair action.
The primary objective of the present invention is to provide a manufacturing process of an IC module which its circuit board need not be specially disposed so as to reduce the manufacturing cost of the circuit board.
It is another objective of the present invention to provide a manufacturing process of an IC module that can effectively enhance the speed for changing the chip thereon.
It is another objective of the present invention to provide a manufacturing process of an IC module that can ensure not to damage the circuit board during changing the chip for repair such that the circuit board can be reused.
It is still another objective of the present invention to provide a manufacturing process of an IC module that can effectively enhance the speed for changing the chip even if the chip has been encapsulated by the resin.
In order to achieve the above objectives, the present invention provides a manufacturing process of an IC module comprising the following steps: (a) providing a circuit board, which has at least one module circuit pattern thereon, said circuit pattern having at least one chip assembly area and an electronic element assembly area; (b) mounting at least one substrate on said at least one chip assembly area; said substrate is provided thereon with at least one connecting circuit pattern which is electrically connected to the at least one module circuit pattern of said circuit board; (c) mounting at least one IC chip on said at least one substrate such that said IC chip is electrically connected to said connecting circuit pattern of the substrate.